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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
11

Beneficial outcomes of recreation at the Eastern Huachuca Mountains, Coronado National Forest

Irani, Jasmine Khushro, 1972- January 1996 (has links)
Leisure opportunities seem necessary for individual well-being, as they provide satisfaction to many levels and types of needs and wants. This research deals with identifying and assessing the beneficial outcomes of those leisure opportunities acquired from various recreational experiences. The study used Brown, Miller, and Carr Canyon in Eastern Huachuca Mountains of the Coronado National Forest in Southern Arizona as study sites for assessing the relationship between experiences and benefits. The findings suggest that there was a 100% congruence between the recreational experiences sought and the ability of these sites to provide them. The correlation between perceived beneficial outcomes of recreational experiences and the visitors' abilities to acquire such outcomes in these settings were significantly positive. The most significant benefit documented in this study was to improve one's physical fitness. It seemed to be positively correlated with each of the four experiences stated in this study, i.e., to learn more about nature, to get away from the usual demands of life, of being in the wilderness area and experiencing a sense of adventure, and spend time with family and/or friends.
12

Public attitudes, wildlife, and recreation management in Pusch Ridge Wilderness, Arizona

Devers, Patrick Kevin January 1999 (has links)
I present model for incorporating public attitudes in wildlife management involving desert bighorn sheep (Ovis canadensis) in Pusch Ridge Wilderness (PRW), Arizona. I conducted a mail survey on 4 user-groups including. The Access Fund (TAF), La Reserve Homeowners Association (LRH), Southern Arizona Hiking Club (SAHC), and white-tailed deer hunters (WTH). Support for translocating sheep into PRW ranged from 59%-80%. Support for banning dogs from PRW to reduce stress to bighorn sheep ranged from 49%-79%. A majority (53%-66%) of each user-group, except WTH supported seasonal closures during lambing season to reduce stress to bighorn sheep. A majority of each user-group (60%-74%) supported using prescribed fires to reduce wildfire hazards and improve habitat for sheep. This information will help agencies develop goals and objectives for bighorn sheep and recreation management in PRW.
13

Belowground carbon fluxes respond to nutrient availability in a northern hardwood forest

Bae, Kikang 03 May 2014 (has links)
<p> Soil respiration is a major flux of carbon to the atmosphere in terrestrial ecosystems. If belowground carbon cycling processes are disrupted, as by N deposition in northern hardwood forests, there could be feedbacks to atmospheric CO<sub>2</sub>. Despite its importance in the global carbon budget, soil respiration is not widely studied across different levels of nutrient availability in soils. In this study, we measured soil respiration across northern hardwood forest sites of differing fertility and age in the White Mountains of New Hampshire. </p><p> Across the range of soil nutrient availability, soil respiration and belowground carbon allocation were lower in sites with relatively low nutrient availability compared with sites categorized as medium or high fertility. Soil respiration and belowground carbon allocation did not differ significantly with forest age. </p><p> Summer soil respiration rate was not correlated to soil P and Ca availability, but was low in soils with high N availability. This result suggests that greater N availability in soils may contribute to less belowground carbon allocation in northern hardwood forests. </p><p> To further study single and synergistic nutrient effects on soil or microbial respiration, nitrogen and phosphorus were applied in treatments of: N-only, P-only, N+P, and control. There were no significant N or P fertilization effects on soil or microbial respiration after two years of fertilization treatment. </p><p> To study microbial respiration alone, five stands (4 plots in each stand) were selected in which living roots were severed by digging trenches. Although total soil respiration did not change after fertilization, the contribution of microbial respiration to soil respiration increased significantly in N+P plots compared to N-only and control plots with trenches. Microbial respiration in laboratory incubations also suggested that there were no discernible changes in Oe and Oa horizons after fertilization. </p><p> Data from this study suggest that nutrient availability, particularly N, can affect soil respiration. The two-year study period was not long enough to detect fertilization effects on soil and microbial respiration, hence long-term tracking of the fertilization treatments in this study will be necessary to determine if belowground carbon flux changes in response to increased N and P availability in soils.</p>
14

FOREST TECHNOLOGY: SELECTED TWO-YEAR PROGRAMS AND THEIR GRADUATES

Unknown Date (has links)
Source: Dissertation Abstracts International, Volume: 29-07, Section: B, page: 2252. / Thesis (Educat.D.)--The Florida State University, 1968.
15

The flora of Mont Rigaud /

Newstrom, Linda E. January 1978 (has links)
No description available.
16

Nocturnal activity of female desert mule deer

Hayes, Charles Laforest, 1966- January 1992 (has links)
I quantified nocturnal activity of female desert mule deer (Odocoileus hemionus crooki) in the Belmont and Bighorn Mountains, Arizona, 1990. I determined seasonal differences in percent of time active and distances moved at night from locations of radio-collared deer. I compared nocturnal home ranges and habitat use to those obtained from daytime locations. Activity differed among seasons (P = 0.046). Nocturnal activity was greatest in spring and summer, and decreased in winter. Movement distances also varied with seasons (P = 0.045). Most of the area of nocturnal home ranges (88%) fell within daytime home ranges. Use of habitat in relation to availability was consistent between day and night for 6 of 8 vegetation associations. Use of disturbed sites increased at night (P < 0.01).
17

Ecology of arctic grayling in Becharof Lake tributaries

Eaton, Dewey Mitchell, 1960- January 1993 (has links)
I studied the grayling populations in 4 tributaries of Becharof Lake. The grayling in Ruth River, and Salmon, Featherly and Becharof Creeks appear to be independent populations, with high fidelity to specific streams. All populations overwintered in the lake and migrated into the streams when water temperatures reached about 2.5 C. These populations contained some of the largest grayling in the state; generally >50% of the population exceeding 6 years in age and had fork lengths >400 mm. Interstream movement rates were about 2%, but intrastream movement was higher (18%). Spring migration into the streams extended from May-July. This extended migration may have invalidated the assumption of a closed population, and resulted in higher than actual estimated abundance. Abundance ranged from a low of 33 grayling/Km in Featherly Creek to a high of 230 grayling/Km in Becharof Creek. Survival rates were similar in all streams.
18

Habitat use and preference of Gila topminnow

Forrest, Robert Eugene, 1965- January 1992 (has links)
The Gila topminnow (Poeciliopsis occidentalis occidentalis) is federally and state listed as endangered. My objectives were to quantify microhabitat use and preference of topminnow in the field and test responses to controlled laboratory settings. In Cienega Creek, topminnow preferred stream margins where the water was calm, shallow, and contained aquatic vegetation. Topminnow were always near the water surface. Water temperature averaged 1-2 C warmer in areas occupied by fish. In outdoor pools, groups of topminnow consistently preferred cover provided over no cover and selected the upper 1/3 of the water column. Plastic strips, elicited the strongest response and styrofoam sheets elicited the weakest response. Topminnow did not show a consistent preference for cover when tested singly in aquaria, but showed a strong preference for calm water. Responses of topminnow to tests in aquaria were not in concordance with behavior observed in Cienega Creek or in tests conducted in outdoor pools.
19

Wild edible plants (WEPs) and their contribution to food security: an analysis of household factors, access and policy in the semi-arid midlands of Kenya

Shumsky, Stephanie January 2013 (has links)
Food insecurity and malnutrition are issues that affect approximately one in seven people worldwide and climate change threatens to increase those risks in the future. Many of the policies that address future food systems emphasize resilience - a combination of flexibility in the face of disturbance and the capacity to adapt to change. In Sub-Saharan Africa many households employ livelihood systems that are highly sensitive to change and cannot adapt well to changing environmental conditions, leaving them vulnerable and reliant on coping strategies. Wild edible plants (WEPs) are a particularly common and effective strategy for coping with food insecurity. This research, conducted in rural Eastern Province, Kenya, suggests that certain demographic characteristics and access conditions are correlated with greater use of WEPs. Food insecure households, and those families lacking off-farm income or with lower levels of assets were found to consume WEPs with greater frequency. Access to WEPs was also a major factor, with smaller farm sizes and increased distance to harvest areas correlated significantly to lower levels of WEP use. After reviewing the existing laws pertaining to State forests, privatization trends of communal land and an increasingly formalized management regime for private land tenure, I find that access to WEPs is declining. Development practitioners', governments' and donor organizations' focus on commercialization and commodity value has led extension agents and land owners to ignore the subsistence value of WEPs, especially for poorer populations. The household characteristics identified in this study are specific enough that they can be used to determine the demographic groups that rely heavily on WEPs, and the access conditions that are likely to increase the ability of those vulnerable groups to employ WEPs as a coping strategy to increase system resilience. Protecting and promoting sustainable use of WEPs could increase the current contribution of these valuable resources to household food security, especially if policies can be tailored for the groups that depend on them the most. / L'insécurité alimentaire et la malnutrition affectent environ une personne sur sept à travers le monde et le changement climatique menace d'accroître ces risques à l'avenir. La plupart des politiques qui concernent les systèmes alimentaires futures mettent en relief la résilience - une combinaison de flexibilité face à la perturbation et la capacité de s'adapter au changement. En Afrique sub-saharienne de nombreux ménages utilisent des stratégies de moyens de subsistance qui sont très sensibles aux changements et ne peuvent bien s'adapter aux conditions environnementales, ce qui les rendent vulnérables et dépendants des stratégies de survie. L'utilisation des plantes sauvages comestibles (WEPs) représente une stratégie particulièrement commune et efficace. Cette recherche réalisée dans la Province de l'Est du Kenya suggère que certaines caractéristiques démographiques et conditions d'accès sont en corrélation avec une augmentation de la consommation de WEPs. Les lois forestières dans les zones de conservation, la privatisation des terres communales, et la formalisation des régimes de gestion contribuent à la réduction d'accès aux ressources WEP, tout en mettant l'accent sur la commercialisation et la valeur de ces produits pour l'export, ce qui a provoqué les agents de vulgarisation et les propriétaires fonciers à ignorer la valeur substantielle des WEPs, en particulier pour les populations les plus pauvres. La protection et la promotion de l'utilisation durable des WEPs pourraient augmenter la contribution actuelle de ces ressources importantes à la sécurité alimentaire des ménages, et d'autant plus si les politiques peuvent être adaptées pour les groupes qui dépendent le plus sur les WEPs.
20

Territorial behaviour of prairie pothole blue-winged teal

Stewart, Gary R. January 1977 (has links)
No description available.

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